JPH0324592B2 - - Google Patents
Info
- Publication number
- JPH0324592B2 JPH0324592B2 JP58104807A JP10480783A JPH0324592B2 JP H0324592 B2 JPH0324592 B2 JP H0324592B2 JP 58104807 A JP58104807 A JP 58104807A JP 10480783 A JP10480783 A JP 10480783A JP H0324592 B2 JPH0324592 B2 JP H0324592B2
- Authority
- JP
- Japan
- Prior art keywords
- tube
- wear
- rubber
- xii
- sectional
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 239000000919 ceramic Substances 0.000 claims description 18
- 239000003795 chemical substances by application Substances 0.000 claims description 5
- 238000007906 compression Methods 0.000 claims description 5
- 238000005086 pumping Methods 0.000 claims description 5
- 230000006835 compression Effects 0.000 claims description 4
- 239000004570 mortar (masonry) Substances 0.000 claims description 4
- 230000015572 biosynthetic process Effects 0.000 claims 1
- 239000000463 material Substances 0.000 description 5
- 230000002265 prevention Effects 0.000 description 5
- 239000012530 fluid Substances 0.000 description 3
- 239000012779 reinforcing material Substances 0.000 description 3
- 238000005452 bending Methods 0.000 description 2
- 239000002131 composite material Substances 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- TWNQGVIAIRXVLR-UHFFFAOYSA-N oxo(oxoalumanyloxy)alumane Chemical compound O=[Al]O[Al]=O TWNQGVIAIRXVLR-UHFFFAOYSA-N 0.000 description 2
- 239000004576 sand Substances 0.000 description 2
- 229910052581 Si3N4 Inorganic materials 0.000 description 1
- 238000005299 abrasion Methods 0.000 description 1
- 239000000853 adhesive Substances 0.000 description 1
- 230000001070 adhesive effect Effects 0.000 description 1
- 229910010293 ceramic material Inorganic materials 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 238000013329 compounding Methods 0.000 description 1
- 230000006837 decompression Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- -1 etc. Chemical compound 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 239000002861 polymer material Substances 0.000 description 1
- 230000003014 reinforcing effect Effects 0.000 description 1
- 238000007789 sealing Methods 0.000 description 1
- HBMJWWWQQXIZIP-UHFFFAOYSA-N silicon carbide Chemical compound [Si+]#[C-] HBMJWWWQQXIZIP-UHFFFAOYSA-N 0.000 description 1
- 229910010271 silicon carbide Inorganic materials 0.000 description 1
- HQVNEWCFYHHQES-UHFFFAOYSA-N silicon nitride Chemical compound N12[Si]34N5[Si]62N3[Si]51N64 HQVNEWCFYHHQES-UHFFFAOYSA-N 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- MTPVUVINMAGMJL-UHFFFAOYSA-N trimethyl(1,1,2,2,2-pentafluoroethyl)silane Chemical compound C[Si](C)(C)C(F)(F)C(F)(F)F MTPVUVINMAGMJL-UHFFFAOYSA-N 0.000 description 1
Landscapes
- Reciprocating Pumps (AREA)
- Rigid Pipes And Flexible Pipes (AREA)
Description
この発明は、ポンプ用チユーブの高圧部におけ
る高圧縮部の局部内面の損傷および摩耗を防止す
るセラミツク層を一体成形した耐摩性特殊チユー
ブに関するものである。
従来、モルタルやコンクリート等を圧送するス
クイーズ型ポンプ車等に使用されるこの系統のチ
ユーブは、弾性高分子物質からなるゴム状物質の
内面ゴムと強力な補強材と外被ゴムとを組み合わ
せたチユーブＴを、第１図、第２図に示すポンプ
車の圧送ユニツトPUの緩衝材としてのゴムパツ
ドRPの溝３内に当接してＵ字状にセツトして使
用されているものである。チユーブＴはすべて補
強材を有するものであるが、以下図示はすべて補
強材を省略したものである。その使用状態は、第
１図（圧送ユニツトPUの作動状態を示す概要縦
断面図）、第２図（チユーブＴがゴムローラーに
て押しつぶされた状態を示す縦断面図）に示すよ
うに、モルタルやコンクリートをコンクリートミ
キサーから圧送ユニツトPUのホツパー１に流し
込み、回転翼２にて、金属のドラム（円筒外壁）
４内のゴムパツドRPの溝３にＵ字状にセツトさ
れたチユーブＴのＢ側内に移送され、その移送さ
れたモルタルやコンクリートは、減圧室１０内
で、駆動歯車６、かみ合い歯車７，８、チエーン
９にて矢印方向（左回転）に回転する２個のロー
ラー５にてチユーブＴを押しつぶしながら矢印方
向（右回転方向）にチユーブＴのＡ側の吐き出し
方向へ圧送されるものである。この圧送される圧
かい（潰）位置を時刻的に時−時−XII時と分
割すると、ローラー５の圧送による内圧上昇は
時位置付近から圧力上昇をはじめ時位置付近か
ら急激に上昇し、時位置からXII時位置までが最
高圧となり、ローラー５がXII時位置を過ぎると内
圧は急に下降し、チユーブのＡ側にて瞬時的に圧
送と吸引が繰り返し行なわれる。
すなわち、XII時位置付近は高圧下に圧縮され、
圧縮度合の大きい部分の内面が、圧縮方向の上下
に局部的摩耗１１（第３図−１、第３図−２参
照）を生起し、時には、流体中の鋭利な角のある
粒子によつて切り込み様摩耗１２（第４図−１、
第４図−２参照）のような状態を形成するもので
あつた。従つて、チユーブが短時間に損傷し使用
不能になるケースが多くみられた。
因つて、この発明は、従来の欠陥を究明し、そ
の欠陥の防止を目差したものである。なお、上記
の第３図−１は、チユーブＴの内面の局部的摩耗
１１を示すチユーブの断面図、第３図−２は、XII
時位置のチユーブの横断面図、第４図−１は同じ
く切り込み様摩耗１２を示すチユーブの断面図、
第４図−２は、XII時位置のチユーブの横断面図で
ある。このチユーブＴ内を圧送されるスラリ
（Slurry）状固形物等の流体中には、非常に鋭利
な角を有する比較的細かい砂粒が混入しているも
のである。このような流体の圧送の場合、XII時位
置において圧送と吸引が繰り返されるものである
が、チユーブＴが連続的に圧縮された直後に復元
しようとする瞬間に、非常に小さい面積の空隙
AG（第５図参照）を生起する。
この小さい空隙AGを通つて、チユーブＴのＡ
側（吐き出し側）の圧力により鋭利な角を有する
小さい砂粒がＢ側へ逆流する際にチユーブＴの内
面ゴムに切り込み様摩耗を生じ、これが損傷の誘
因となり、成長して補強層を破壊して早期損傷に
至るものと考えられる。
そこで、この損傷の根源である基本的誘因を解
消する方法を探求の結果、全くゴムとは異質の金
属セラミツクを局部的に複合することによつて、
著しく改良されることの結論を得たものである。
すなわち、これによつて、早期の局部摩耗、偏
摩耗を根本的に解決し得たものである。
次に、この発明の耐摩性特殊チユーブの態様に
ついて詳述する。
このチユーブＴの損傷の誘因箇所は、２個のロ
ーラー５が、時位置とXII時位置を結んだ直線上
に来た時のXII時位置の前後の範囲に、損傷の根源
となる局部摩耗並びに切り込み様摩耗が発生する
知見に基づいて、その局部的誘因を防止すること
を痛感し、その防止の適材を探究の結果、セラミ
ツクが局部的要因を排除する適材であるとの結論
に到達したものである。
セラミツク材料には、炭化珪素質グレーン、炭
化チタン、窒化珪素（Si3N4）、酸化アルミニウ
ム等があるが、特に、耐摩性、曲げ強度等の点か
ら酸化アルミニウム系統が好ましい。
なお、セラミツクは加工条件により非常にスム
ースな表面が得られるため、ローラーの圧接状態
においても十分なチユーブとしての必要なシール
力（通常20〜30Kg／cm2）が得られる。
また、セラミツクとゴムとは、接着剤によつて
加硫一体成形によつて、10〜20Kg／cm2の強力な接
着が得られる。
なお、ゴムと接着して複合化するセラミツク
は、圧縮および曲げによつて破損しないように、
小片の板状に形成されるもので、その小片の大き
さは、一例として、たとえば、幅５〜15mm×長さ
５〜10mm×厚さ２〜４mmのものを、圧送ユニツト
PUにＵ字状に設定された時のチユーブＴのXII時
位置の前後の範囲の内面ゴムの上下に一体接着す
るものである。
そのセラミツク１３の小片を長手方向に配列し
て、第６図−１、第６図−２に示すように配列ユ
ニツトUAを、XII時位置の前後付近の長手方向限
定範囲の上下２箇所に、セラミツク小片を間隔を
置いて長手方向に帯状的状態に内面ゴムと加硫接
着して、ゴムと一体的に設定して、チユーブの圧
縮時の横断面中央部に、圧縮直後の復元瞬時に生
起される空〓AG部に対応する、上下２箇所の長
手方向限定範囲に、摩損防止ゾーンWRZを形成
するものである。
なお、第６図−１は、チユーブＴの局部内面に
おけるセラミツク１３の配列ユニツトUAの設定
状態を示した断面図、第６図−２はXII−XII線断面
図である。
このセラミツク１３の配列ユニツトUAからな
る摩損防止ゾーンWRZの範囲は、チユーブのサ
イズ、使用条件、ポンプの種類等によつて異なる
が、XII時位置の前後の範囲、すなわち、通常±50
〜150mm程度に設定する。
第７図−１は、摩損防止ゾーンWRZの圧縮時
の状態を縦断面にて示したもので、第７図−２は
XII時位置の圧縮時の横断面を示したものである。
この発明の耐摩性特殊チユーブは、その内面ゴ
ムにセラミツク１３の配列ユニツトUAを上下に
形成するものであるため、内面ゴムのセラミツク
の配列位置が簡単に判定出来るように、チユーブ
の外面に軸線方向に２本の朱色等の識別線を入れ
るとか、または、チユーブを自然に曲げた時に、
セラミツクの配列ユニツトUAが上下になるよう
に偏肉のチユーブとするように考慮してもよい。
次に、この発明のチユーブと従来のチユーブと
の比較試験の結果を示す。
実施の条件
圧送材料 モルタル
チユーブサイズ
50mmφ×長さ1500mm×肉厚15mm
ポンプ 7HP、45rpm
圧送ユニツト
ドラム径 580mmφ
ローラー径 120mmφ×長さ115mm
The present invention relates to a special wear-resistant tube integrally molded with a ceramic layer that prevents damage and wear on the local inner surface of a high-compression section in a high-pressure section of a pump tube. Conventionally, this type of tube, which is used in squeeze-type pump trucks for pumping mortar, concrete, etc., is a tube that combines an inner rubber made of a rubber-like material made of an elastic polymer material, a strong reinforcing material, and a rubber outer cover. The T is used by being set in a U-shape in contact with the groove 3 of the rubber pad RP as a buffer material of the pressure feeding unit PU of the pump car shown in FIGS. 1 and 2. All of the tubes T have reinforcing materials, but the reinforcing materials are omitted in all illustrations below. Its use condition is as shown in Fig. 1 (schematic vertical cross-sectional view showing the operating condition of the pressure feeding unit PU) and Fig. 2 (vertical cross-sectional view showing the state in which the tube T is crushed by a rubber roller). The concrete is poured from a concrete mixer into the hopper 1 of the pressure feeding unit PU, and the rotor 2 transfers it to a metal drum (cylindrical outer wall).
The mortar and concrete are transferred to the B side of the tube T set in a U-shape in the groove 3 of the rubber pad RP in the rubber pad RP in the decompression chamber 10. In the chain 9, the tube T is compressed by two rollers 5 rotating in the direction of the arrow (rotation to the left) and is forced to be fed in the direction of the arrow (rotation to the right) toward the discharge direction of the A side of the tube T. If we divide this pressure pumping (squeezing) position into hours - hours - The maximum pressure is from the position to the XII o'clock position, and when the roller 5 passes the XII o'clock position, the internal pressure suddenly drops, and pressure feeding and suction are repeated instantaneously on the A side of the tube. In other words, the area around the XII o'clock position is compressed under high pressure,
The inner surface of the highly compressed part causes localized wear 11 (see Figures 3-1 and 3-2) above and below the compression direction, and is sometimes caused by sharp angular particles in the fluid. Notch-like wear 12 (Fig. 4-1,
(See Figure 4-2). Therefore, there were many cases where the tube was damaged in a short period of time and became unusable. Therefore, the present invention aims to investigate the conventional defects and prevent them. In addition, the above-mentioned FIG. 3-1 is a sectional view of the tube showing local wear 11 on the inner surface of the tube T, and FIG. 3-2 is a cross-sectional view of the tube
FIG. 4-1 is a cross-sectional view of the tube in the same position showing notch-like wear 12;
FIG. 4-2 is a cross-sectional view of the tube at the XII o'clock position. The fluid such as slurry-like solids that is pumped through the tube T contains relatively fine sand grains having very sharp edges. In the case of such fluid pumping, pumping and suction are repeated at the XII o'clock position, but at the moment when the tube T tries to restore itself immediately after being continuously compressed, a gap of a very small area is created.
AG (see Figure 5) occurs. A of the tube T passes through this small gap AG.
When small sand grains with sharp edges flow back to the B side due to the pressure on the side (discharge side), they cause cut-like wear on the inner rubber of the tube T, which causes damage, grows, and destroys the reinforcing layer. It is thought that this will lead to early damage. Therefore, as a result of searching for a method to eliminate the basic cause that is the root cause of this damage, we found that by locally compounding metal ceramic, which is completely different from rubber,
The conclusion was that it was significantly improved. That is, with this, early local wear and uneven wear can be fundamentally solved. Next, aspects of the wear-resistant special tube of the present invention will be described in detail. The points that cause damage to the tube T are local wear and damage that are the source of damage in the area before and after the XII o'clock position when the two rollers 5 come on a straight line connecting the o'clock position and the XII o'clock position. Based on the knowledge that notch-like wear occurs, we were acutely aware of the need to prevent its local triggers, and as a result of searching for the appropriate material to prevent it, we came to the conclusion that ceramic is the appropriate material to eliminate the local cause. It is. Ceramic materials include silicon carbide grains, titanium carbide, silicon nitride (Si 3 N 4 ), aluminum oxide, etc., and aluminum oxide is particularly preferred from the viewpoint of wear resistance, bending strength, etc. In addition, since ceramic has a very smooth surface depending on processing conditions, sufficient sealing force (usually 20 to 30 kg/cm 2 ) necessary for a tube can be obtained even when pressed by a roller. Further, by integrally vulcanizing ceramic and rubber with an adhesive, a strong bond of 10 to 20 kg/cm 2 can be obtained. In addition, ceramics that are bonded to rubber to form a composite are made with special care to prevent them from being damaged by compression and bending.
It is formed into a small plate shape, and the size of the small piece is, for example, 5 to 15 mm wide x 5 to 10 mm long x 2 to 4 mm thick, and the size of the small piece is, for example, 5 to 15 mm wide x 5 to 10 mm long x 2 to 4 mm thick.
It is integrally bonded to the top and bottom of the inner rubber in the area before and after the XII o'clock position of the tube T when it is set in a U-shape on the PU. The small pieces of the ceramic 13 are arranged in the longitudinal direction, and as shown in Fig. 6-1 and Fig. 6-2, the arrangement unit UA is placed at two locations above and below within a limited range in the longitudinal direction near the front and rear of the XII o'clock position. Ceramic pieces are vulcanized and bonded to the inner rubber in the form of strips at intervals in the longitudinal direction, and are set integrally with the rubber, so that when the tube is compressed, it instantly returns to its original state at the center of the cross section when it is compressed. A wear prevention zone WRZ is formed in a limited range in the longitudinal direction at two locations, upper and lower, corresponding to the empty AG section. Note that FIG. 6-1 is a sectional view showing the setting state of the arrangement unit UA of the ceramics 13 on the local inner surface of the tube T, and FIG. 6-2 is a sectional view taken along the line XII--XII. The range of the wear prevention zone WRZ consisting of the array unit UA of the ceramic 13 varies depending on the size of the tube, usage conditions, type of pump, etc., but it is usually the range before and after the XII position, that is, ±50
Set it to about ~150mm. Figure 7-1 shows the state of the wear prevention zone WRZ when it is compressed in longitudinal section, and Figure 7-2 shows
This figure shows a cross section when compressed at the XII o'clock position. The wear-resistant special tube of the present invention has array units UA of ceramics 13 formed vertically on its inner rubber surface. Therefore, in order to easily determine the arrangement position of the ceramics 13 on the inner surface rubber, the outer surface of the tube has an axially arranged array unit UA. If you put two identification lines such as vermilion on the tube, or if you bend the tube naturally,
It may be considered to use a tube with uneven thickness so that the ceramic array units UA are placed one above the other. Next, the results of a comparative test between the tube of the present invention and a conventional tube will be shown. Implementation conditions Pressure feeding material Mortar tube size 50mmφ x length 1500mm x wall thickness 15mm Pump 7HP, 45rpm Pressure feeding unit Drum diameter 580mmφ Roller diameter 120mmφ x length 115mm
【表】
以上のとおり、第１表に示すように、ゴムとセ
ラミツクとの複合チユーブの場合は、従来のチユ
ーブの耐久寿命に比較し、抜群の効果を発揮する
ものとなつた。[Table] As shown in Table 1, the composite tube of rubber and ceramic exhibits outstanding effects compared to the durability life of conventional tubes.
第１図は、圧送ユニツトの作動状態を示す概要
縦断面図、第２図は、圧送ユニツトにおいてチユ
ーブＴがゴムローラーにて押しつぶつされた状態
を示す横断面図、第３図−１は、内面の局部的摩
耗を示すチユーブの断面図、第３図−２は、XII−
XII線横断面図、第４図−１は、内面の切り込み様
摩耗を示すチユーブの断面図、第４図−２は、XII
−XII線横断面図、第５図は、空隙発生の一例を示
すチユーブの断面図、第６図−１は、セラミツク
の配列ユニツトの設定状態を示すチユーブの断面
図、第６図−２は、XII−XII線断面図、第７図−１
は、摩損防止ゾーンの圧縮時の縦断面図、第７図
−２は、XII時位置の横断面図である。
Ｔ……チユーブ、UA……配列ユニツト、
WRZ……摩損防止ゾーン、１１……局部的摩耗、
１２……切り込み様摩耗、１３……セラミツク、
PU……圧送ユニツト、AG……空〓。
Fig. 1 is a schematic vertical cross-sectional view showing the operating state of the pressure feeding unit, Fig. 2 is a cross-sectional view showing the state in which the tube T is crushed by a rubber roller in the pressure feeding unit, and Fig. 3-1 is a schematic longitudinal sectional view showing the operating state of the pressure feeding unit. , a cross-sectional view of the tube showing local wear on the inner surface, FIG. 3-2 is XII-
4-1 is a cross-sectional view of the tube showing notch-like wear on the inner surface, and FIG. 4-2 is a cross-sectional view taken along line XII.
-XII line cross-sectional view, FIG. 5 is a cross-sectional view of the tube showing an example of generation of voids, FIG. 6-1 is a cross-sectional view of the tube showing the setting state of the ceramic arrangement unit, and FIG. 6-2 is , XII-XII line sectional view, Figure 7-1
7-2 is a longitudinal cross-sectional view of the abrasion prevention zone when compressed, and FIG. 7-2 is a cross-sectional view at the XII o'clock position. T...tube, UA...array unit,
WRZ...Wear prevention zone, 11...Local wear,
12...notch-like wear, 13...ceramic,
PU...Pulse feeding unit, AG...Empty.
Claims (1)
用チユーブにおいて、圧送ユニツトPUのXII時位
置の前後付近の長手方向限定範囲の、局部的摩
耗、切り込み様摩耗等の発生しやすい、上下２箇
所のチユーブ内面に、接触面をスムースに加工し
たセラミツク小片を、間隔を置いて、長手方向に
帯状的状態に配列して、内面ゴムと加硫接着し
て、セラミツクの配列ユニツトUAをゴムと一体
的に設定して、チユーブの圧縮時の横断面中央部
に、圧縮直後の復元瞬時に生起される空〓AG部
に対応する、上下２箇所の長手方向限定範囲に、
摩損防止ゾーンを形成したことを特徴とする耐摩
性特殊チユーブ。1. In a pump tube that pumps concrete, mortar, etc., the inner surface of the tube is placed at two locations, upper and lower, where localized wear, notch-like wear, etc. are likely to occur in a limited range in the longitudinal direction around the XII position of the pumping unit PU. , ceramic pieces with smooth contact surfaces are arranged in a strip-like manner in the longitudinal direction at intervals, and are vulcanized and bonded to the inner rubber, and the ceramic arrangement unit UA is set integrally with the rubber. Then, in the center of the cross section of the tube during compression, there are two limited areas in the longitudinal direction, upper and lower, corresponding to the empty AG part that occurs at the instant of restoration immediately after compression.
A special wear-resistant tube characterized by the formation of an anti-wear zone.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10480783A JPS59231185A (en) | 1983-06-11 | 1983-06-11 | Wear proof special tube |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10480783A JPS59231185A (en) | 1983-06-11 | 1983-06-11 | Wear proof special tube |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS59231185A JPS59231185A (en) | 1984-12-25 |
| JPH0324592B2 true JPH0324592B2 (en) | 1991-04-03 |
Family
ID=14390691
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP10480783A Granted JPS59231185A (en) | 1983-06-11 | 1983-06-11 | Wear proof special tube |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS59231185A (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101788087B (en) * | 2010-03-12 | 2012-05-23 | 夏德坤 | Preparation method of ceramic rubber wear-resisting pipe |
| CN104154348A (en) * | 2014-08-06 | 2014-11-19 | 杨继广 | Water pipe special for peristaltic pump |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS514609A (en) * | 1974-05-21 | 1976-01-14 | Nitsukiso Eikopu Kk | Honpuyochuubuoyobi koreoshosuruhonpu |
-
1983
- 1983-06-11 JP JP10480783A patent/JPS59231185A/en active Granted
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS514609A (en) * | 1974-05-21 | 1976-01-14 | Nitsukiso Eikopu Kk | Honpuyochuubuoyobi koreoshosuruhonpu |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS59231185A (en) | 1984-12-25 |
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